Spiders are arachnids, a class of arthropods that also includes scorpions, mites, and ticks. There are more than 45,000 known species of spiders, found in habitats all over the world. There’s a spider with a cartoonish butt, spiders that can jump on demand, and cannibal spiders that look like pelicans.

Spiders range in size from the tiny Samoan moss spider, which is .011 inch long, to the massive Goliath birdeater, a tarantula with a leg span of almost a foot.

For most people, the thought of spiders conjures up images of tarantulas, wolf spiders, and other (seemingly) fearsome creatures. Though all spiders have venom to one degree or another, only a handful are dangerous to